Water cement ratio bs flags

[iain123]

Hi Group

I wanted to find out the water to cement ratio, w/c used in British Standard Flag stones. The sort that councils use.

I believe they are made using a dry mix hydraulically rammed/pressed into the mould. The Flag can be turned out of the mould immediately.

To compare w/c with my superplastizised wet mix.

Thanks
Iain

[Tony McC]

Each manufacturer uses a "secret" recipe. They won't reveal what ratio of aggregates they use, what blend of cement, what additives are included, nor what w/c ratio - it's commercially sensitive information. The BS/EN dictates what the results must be, in terms of flexural and compressive strength, etc., but it does not, and could not, dictate what concrete has to be used.

Have a read of this FAQ for fuller info.

I've been in countless block making and flag making plants, in countries throughout Europe and North America. Many of the BS-type flags are made using a fairly high slump concrete that is pressed hydraulically to remove "excess" water, but some plants, particularly modern plants making small element flags are using a semi-dry mix, not unlike that used for block paving.